Intervertebral implant and insertion device therefor

ABSTRACT

An intervertebral implant includes a body with a first face, a second face connected to the first face, and an axis of rotation. The body defines a hollow space for connecting to an insertion device, the hollow space being accessible through an opening formed between the first and second faces. The opening is elongate and extends around the axis of rotation to facilitate pivoting of the implant relative to the insertion device about the axis of rotation to a first angular position and a second angular position. The implant further includes a first abutment surface that engages the insertion device in a form-fit manner at the first angular position, and a second abutment surface that engages the insertion device in a form-fit manner at the second angular position. The opening can also engage the insertion device to hold the implant at at least one additional angular position.

CROSS-REFERENCE TO RELATED APPLICATION(S)

The present application claims priority to and the benefit of U.S.Provisional Patent Application No. 62/901,944, filed Sep. 18, 2019, thecontents of which are hereby incorporated by reference in theirentirety, and claims priority from European Patent Application EP 19 198123.2, filed Sep. 18, 2019, the contents of which are herebyincorporated by reference in their entirety.

BACKGROUND Field

The application relates to an intervertebral implant and an insertiondevice for such an intervertebral implant. The intervertebral implantand the insertion device may be used, for example, for spinal fusion incases involving a damaged intervertebral disk.

Description of Related Art

Lumbar or thoracic interbody fusion surgery is one of the most commonlyperformed spinal fusion surgeries using an instrument. Some knownsurgical approaches for interbody fusion of the lumbar spine includeposterior lumbar interbody fusion (PLIF), transforaminal lumbarinterbody fusion (TLIF), anterior lumbar interbody fusion (ALIF),antero-lateral ALIF, and lateral interbody fusion.

An intervertebral implant and a device for inserting the same that are,for example, suitable for TLIF are described in US 2017/0056194 A1. Theintervertebral implant has a top surface, a bottom surface, a sidewallextending between the top surface and the bottom surface, and a hollowspace formed within the intervertebral implant and accessible through anelongate opening extending through a recessed portion of the sidewall.The hollow space is shaped to receive an engagement portion of a driveshaft of an insertion tool. The intervertebral implant includes at leasttwo guiding surfaces facing each other and configured for slidingengagement by a portion of a sleeve of the insertion tool that movablyholds the drive shaft.

SUMMARY

It is an object of the invention to provide an improved or alternativeintervertebral implant and an insertion device that has an increasedfield of application.

The intervertebral implant is designed to permit pivoting of theinsertion device relative to the intervertebral implant and locking ofthe intervertebral implant relative to the insertion device at at leasttwo pivot positions, for example, by a form-fit connection. Such aform-fit connection is more robust compared to a force-fit connectionthat is based on friction. This enhances safety during insertion of theintervertebral implant, where often large forces are needed.

Moreover, it is possible to insert the intervertebral implant with theinsertion device at a fixed position defined by the form-fit connectionand, if necessary, to adjust the position of the implant after releasingthe form-fit connection, and/or to pivot the implant relative to theinsertion device while the implant is still safely connected thereto. Bymeans of such a procedure, corrections of the position of the implantcan be made.

According to a further embodiment, the intervertebral implant may havemore than two different surfaces for defining different pivot angles fora form-fit connection between the intervertebral implant and theinsertion device. Therefore, with a single intervertebral implant,different access paths to the intervertebral space may be possible anddifferent surgical techniques can be implemented. Hence the field ofapplication of the intervertebral implant can be further increased.

According to a still further embodiment, the intervertebral implant mayhave at least one guiding surface for pivoting of the intervertebralimplant and the insertion device relative to each other along theguiding surface, and for frictional clamping of the implant and theinsertion device with respect to each other at a particular positionalong the cooperating guiding surfaces.

According to a still further embodiment, the intervertebral implant mayinclude further receiving sections for receiving the insertion device ina non-pivotable manner at other locations on the implant.

According to a still further embodiment, the intervertebral implant canbe a dummy implant or testing implant that is used for a trialprocedure, before inserting a permanent intervertebral implant in apatient's body.

Thus, the intervertebral implant can be used, for example, for varioussurgical procedures, such as TLIF, ALIF, antero-lateral ALIF, PLIF, andlateral interbody fusion, but is not restricted thereto, using the sameintervertebral implant and insertion device. Due to the increasedpossibilities of connecting the implant to the insertion device, theimplant may be particularly useful in cases with difficult anatomicalcircumstances, such as in anterior and lateral approaches to the spine.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features and advantages will become apparent from the detaileddescription of embodiment by means of the accompanying drawings. In thedrawings:

FIG. 1 shows a perspective view of a system including an intervertebralimplant according to a first embodiment with an insertion deviceconnected thereto.

FIG. 2 shows a perspective view of the intervertebral implant of FIG. 1from one side, showing an elongate opening for connection with theinsertion device.

FIG. 3 shows a perspective view of the intervertebral implant of FIGS. 1and 2 from another side, showing a further opening for connection withthe insertion device.

FIG. 4 shows a perspective view of a front portion of a drive shaft ofthe insertion device of FIG. 1.

FIG. 5 shows a side view of the front portion of the drive shaft of FIG.4.

FIG. 6 shows a side view of the front portion of the drive shaft of FIG.5 rotated by 90°.

FIG. 7 shows a perspective view of a front portion of a guiding sleeveof the insertion device of FIG. 1.

FIG. 8 shows a side view of the front portion of the guiding sleeve ofFIG. 7.

FIG. 9 shows a side view of the front portion of the guiding sleeve ofFIG. 8 rotated by 90°.

FIGS. 10a to 10c show perspective views of steps for connecting thefront portion of the drive shaft of the insertion device of FIGS. 4 to 6to the intervertebral implant of FIGS. 1 to 3.

FIGS. 11a to 11d show cross-sectional views of steps for connecting afront portion of the insertion device to the intervertebral implant,wherein the cross-section is taken in a plane extending through theintervertebral implant and including a longitudinal axis of theinsertion device.

FIG. 12 shows a perspective view of a form-fit connection between theintervertebral implant and the insertion device, wherein the insertiondevice forms an angle of substantially 45° with a longitudinal axis ofthe intervertebral implant.

FIG. 13 shows a perspective view of a form-fit connection between theintervertebral implant and the insertion device, wherein the insertiondevice forms an angle of substantially 90° with the longitudinal axis ofthe intervertebral implant.

FIG. 14 shows a perspective view of a form-fit connection between theintervertebral implant and the insertion device, wherein the insertiondevice forms an angle of substantially 0° with the longitudinal axis ofthe intervertebral implant.

FIG. 15 shows a perspective view of a connection between theintervertebral implant and the insertion device, wherein the insertiondevice is at a position relative to the intervertebral implant thatpermits rotating and clamping of the intervertebral implant by friction.

FIG. 16 shows a cross-sectional view of the connection between theintervertebral implant and the insertion device forming an angle ofsubstantially 90°, for example, as shown in FIG. 13.

FIG. 17 shows a cross-sectional view of the connection between theintervertebral implant and the insertion device forming an angle ofsubstantially 0°, for example, as shown in FIG. 14.

FIG. 18 shows a cross-sectional view of the connection between theintervertebral implant and the insertion device that permits adjustmentsto various intermediate positions, and frictional clamping of theimplant and the insertion device at intermediate positions, for example,as shown in FIG. 15.

FIG. 19 shows a perspective view of the intervertebral implant with theinsertion device connected to a further receiving portion.

FIG. 20 shows a cross-sectional view of the intervertebral implant withthe insertion device connected to the further receiving portion as shownin FIG. 19.

FIG. 21 shows a perspective view of the intervertebral implant with theinsertion device connected to a still further receiving portion.

FIG. 22 shows a cross-sectional view of the intervertebral implant withthe insertion device connected to the still further receiving portion asshown in FIG. 21.

FIG. 23 shows a perspective view of a further modified embodiment of theintervertebral implant that is formed as an ALIF intervertebral implant.

FIG. 24 shows a perspective view of the intervertebral implant of FIG.23 with the insertion device connected thereto.

FIG. 25 shows a perspective view from a top of the intervertebralimplant and the connected insertion device as shown in FIG. 24.

DETAILED DESCRIPTION

FIG. 1 shows a perspective view of an intervertebral implant and aninsertion device 100 for inserting the intervertebral implant 1 into anintervertebral space. The intervertebral implant 1 has a body includinga substantially vertical sidewall 2 defining a height of theintervertebral implant 1. The sidewall 2 is formed monolithically withan inner solid portion 3 and encloses one or more inner hollow spaces 4.The hollow spaces 4 are open towards an upper face 5 a and a lower face5 b of the intervertebral implant 1.

In greater detail, the sidewall 2 is formed by a front wall 2 a, anopposite back wall 2 b, a right sidewall 2 c, and a left sidewall 2 d,which are monolithically formed, such that the right and left sidewallsconnect the front wall 2 a and the back wall 2 b with each other. Thefront wall 2 a represents an anterior wall and the back wall 2 brepresents a posterior wall of the intervertebral implant 1. The frontwall 2 a and the back wall 2 b may be longer than the right sidewall 2 cand the left sidewall 2 d, so that the intervertebral implant has anelongate outer contour. In the embodiment shown, the front wall 2 a andthe back wall 2 b are substantially parallel to each other and define alongitudinal central axis LI of the intervertebral implant (indicated inFIG. 11a ). Optionally, inner walls 6 a, 6 b may extend in an arc-shapedmanner from the front wall 2 a to the back wall 2 b. Both inner walls 6a, 6 b may be symmetric with respect to a sagittal plane S (indicated inFIG. 11a ) that extends vertically through centers of the front wall 2 aand the back wall 2 b. The solid portion 3 extends from the front wall 2a to a distance from the back wall 2 b, and has a length such thatreceiving portions in the form of recesses, as further described below,can be formed in the solid body 3 with depths sufficient for engagementwith the insertion device 100. The sidewall 2 may have such a heightthat the top surface 5 a and the bottom surface 5 b extend above thesolid portion 3.

The hollow spaces 4 are configured to be filled with bone graftmaterial. Further, engagement portions, for example, teeth 7, may beprovided on the upper face 5 a and the lower face 5 b of theintervertebral implant, which may facilitate penetration into the endplates of adjacent vertebral bodies. The front wall 2 a and the backwall 2 b may have different heights, such that the top face 5 a and thebottom face 5 b form an angle, resulting in the intervertebral implant 1having a wedge shape.

As can be seen in detail in particular in FIG. 2, at the transition ofthe front wall 2 a to the right sidewall 2 c, a recess 10 is providedthat forms an elongate opening 11 in the sidewall 2. The recess 10defines a hollow space within the intervertebral implant 1 for receivinga portion of the insertion device. The recess 10 extends into the solidportion 3 and forms a corner with an angle of substantially 90° degreestherein. Thereby, left and right end walls of the recess 10 form anangle of substantially 90°. The recess 10 and the opening 11 may beprovided at a middle of the sidewall 2 in the height direction.

A width of the recess 10 in the height direction is such that anengagement portion of the insertion device can be introduced in oneorientation but cannot be introduced in a tilted orientation. Top andbottom walls of the recess 10 may be planar, and may extendsubstantially parallel to each other and substantially perpendicular tothe sidewall 2. The opening 11 extends in a circumferential directionfrom the front wall 2 a over a corner between the front wall 2 a and theright sidewall 2 c into the right sidewall 2 c. Hence, the elongateopening 11 and the recess 10 have a size such that a drive shaft of theinsertion device can assume an angle as small as about 0° and an angleas large as about 90° with the central longitudinal axis LI of theintervertebral implant 1.

In the inside corner of the recess 10, a spherically-shaped recess 12 isformed that is configured to pivotably receive the engagement portion ofthe insertion device 100. A radius of the spherically-shaped recess 12matches a radius of an outer surface of the engagement portion of thedrive shaft. The spherical recess 12 is sized to permit the engagementportion of the insertion device to pivot therein in an angular range ofabout 90° or more. An axis R extending through a center of thespherically-shaped recess 12 and parallel to the sidewall 2 forms anaxis of rotation, and more specifically a pivot axis for pivotalmovement between the intervertebral implant 1 and the insertion device100.

The sidewall 2 has, in the region of the elongate opening 11, outersurfaces that are shaped to provide abutment surfaces for the insertiondevice to achieve a form-fit engagement and/or to provide guidingsurfaces for pivotal movement of the insertion device. As can be seen ingreater detail in FIG. 11a , the sidewall 2 protrudes outward in theregion of the recess 10 in an substantially polygonal contour due to thepresence of the abutment surfaces.

Referring in particular to FIGS. 2, 3 and 11 a, a first abutment surface21 is provided around the lateral edge of the elongate opening 11 thatextends into the right sidewall 2 c. The first abutment surface 21 issubstantially planar and is configured to provide a form-fit engagementwith the insertion device when an angle of 0° is formed between acentral longitudinal axis L of the insertion device (see FIGS. 4 to 8)and the central longitudinal axis LI of the intervertebral implant. Asecond abutment surface 22 is provided around the opposite lateral edgeof the elongate opening 11 that extends into the front wall 2 a. Thesecond abutment surface 22 is substantially planar and is configured toprovide a form-fit engagement with the insertion device when an angle of90° is formed between the central longitudinal axis L of the insertiondevice and the central longitudinal axis LI of the intervertebralimplant 1. A third abutment surface 23 extends around substantially acenter of the opening 11 and forms an angle of 45° with the firstabutment surface 21 and the second abutment surface 22. Hence, the thirdabutment surface 23 is configured to provide a form-fit engagement withthe insertion device when an angle of 45° is formed between the centrallongitudinal axis L of the insertion device and the central longitudinalaxis LI of the intervertebral implant 1.

The sidewall 2 further includes a first guiding surface 24 that isprovided between the first abutment surface 21 and the third abutmentsurface 23, and that is cylindrical with a cylinder axis being coaxialwith the rotational axis R. A second guiding surface 25 is providedbetween the second abutment surface 22 and the third abutment surface23, and is also cylindrical with a cylinder axis that is coaxial withthe rotational axis R. The first and second guiding surfaces 24, 25allow a guided rotational, and more particularly a pivotal, movementbetween the intervertebral implant 1 and the insertion device 100 whenthe insertion device is connected and, for example, slightlyfrictionally clamped to the intervertebral implant 1.

Optionally the intervertebral implant 1 may include further receivingportions, for example, recesses in the sidewall 2 for connection withthe insertion device 100 to permit the placement of the intervertebralimplant with the insertion device using various other surgicalapproaches. In the embodiment shown, the intervertebral implant has anadditional recess 30 at substantially the center of the front wall 2 aand an additional recess 30′ at the left sidewall 2 d.

The recesses 30, 30′ each have an overall inner cross-section thatcorresponds to a circle, with cut away opposite sides so as to providean elongate opening 31 with flat upper and lower edges that are parallelto the upper and lower edges of the sidewall 2. The size of the recesses30, 30′ is such that the engagement portion of the drive shaft can beinserted in one orientation, but cannot be inserted in a tiltedorientation. As shown in greater detail, for example, in FIGS. 11a to11c , each recess 30, 30′ has an inner spherically-shaped recess 32, theradius of which matches the radius of the engagement portion of thedrive shaft, so that the engagement portion can be rotated therein toassume a 90° tilted orientation.

Turning now to FIGS. 1 to 8, the insertion device 100 will be described.The insertion device 100 includes a drive shaft 110, a guiding sleeve120 that receives the drive shaft 110 therein, a handle 130, a rotationactuating button 135, and an axial position adjusting device 140. Thedrive shaft 110 is movably guided within the guiding sleeve 120 and maybe advanced or retracted with respect to the guiding sleeve 120 byactuating the axial position adjusting device 140. Further, the driveshaft 110 may be rotated by actuating the rotation actuating button 135.It shall be noted that axial displacement of the drive shaft androtation of the drive shaft may be achieved in various other ways.

The drive shaft 110 defines a longitudinal axis L of the insertiondevice, and has a front portion which is shown in greater detail inFIGS. 4 to 6. The front portion includes an engagement portion 111 witha spherical surface 112 that has the shape of a segment of a sphere. Thespherical surface 112 may be formed by removing opposite segments of thesphere to yield opposite flat surfaces 113. Hence, the engagementportion 111 has a flattened shape with a thickness between the flatsurfaces 113 that is slightly smaller than a vertical height of theelongate opening 11 and heights of the openings 31 of the optionalrecesses 30, 30′. This permits insertion of the engagement portion 111into the recess 10 and optionally into the recesses 30, 30′ of theintervertebral implant 1, in an orientation where the flat surfaces 113extend perpendicular to the height direction of the sidewall 2.

On at least one, and preferably on both, of the flat surfaces 113, alongitudinally extending positioning mark 114 is provided, that extendsparallel to the central longitudinal axis L of the insertion device.

The engagement portion 111 is connected to a main portion 115 via a neckportion 116. The neck portion 116 has an outer diameter that is smallerthan the maximum diameter of the spherical surface portion 112 of theengagement portion 111. The main portion 115 may have a greater diameterthan the neck portion 116. The spherical segment-shaped portion 112 ofthe engagement portion 111 has a size such that, once portion 112 hasbeen inserted into the recess 10 and engages the spherical recess 12 orinto one of the recesses 30, 30′ and engages a spherical recess 32,portion 112 can be tilted by 90° so that the engagement portion 111 isheld in but can still pivot in the spherical recess 12 or in one of thespherical recesses 32.

The front portion of the guiding sleeve 120 is shown in greater detailin FIGS. 7 to 9. When the drive shaft 110 is arranged in the guidingsleeve 120, the engagement portion 111 protrudes out of the frontportion of the guiding sleeve 120. Two opposite cylindrical projections122 form the outermost end of the guiding sleeve 120. The cylindricalprojections 122 have a size such that they are insertable into therecesses 10, 30, 30′, respectively. An end face of the tubular guidingsleeve 120 includes a planar surface 123 and a concave, and morespecifically a cylindrical surface 124 that is arranged between the twoprojections 122 and that has a cylinder axis which is perpendicular tothe central longitudinal axis L. The planar surface 123 thus formsadjacent each projection 122 an abutment surface for abutting againstthe first or the second or the third abutment surfaces at the sidewall 2of the intervertebral implant 1 when the guiding sleeve 120 is pressedagainst the sidewall 2. The cylindrical surface 124 forms a guidingsurface that is configured to cooperate with the first or the secondguiding surfaces 24, 25 at the sidewall 2 of the intervertebral implantto permit a guided rotational movement of the intervertebral implantrelative to the insertion device. Hence, a radius of the cylindricalguiding surface 124 corresponds to a radius of the cylindrical guidingsurfaces 24, 25 on the sidewall of the intervertebral implant 1.

At an outer wall of the guiding sleeve 120 adjacent to the cylindricalprojections 122 in a longitudinal direction, two opposite positioningflat surfaces 125 may be provided. The positioning flat surfaces 125indicate the position of the cylindrical projections 122, and may servefor orienting the insertion device correctly during connection with theintervertebral implant. Moreover, at least one longitudinally extendingpositioning mark 126 at an outside of the front portion of the guidingsleeve 120 may further be provided that is 90° offset from thepositioning flat surfaces 125 and that indicates the position of thecylindrical guiding surface 124.

When the drive shaft 110 is inserted into the guiding sleeve 120 and theengagement portion 111 projects out of the front portion of the guidingsleeve 120, the drive shaft 110 may be pushed forward and retracted byactuating the axial position adjustment device 140. The size of theprojections 122 is such that the engagement portion 111 can only beretracted between the projections 122 in a 90° upright position of theengagement portion 111.

The intervertebral implant 1 may, for example, be made of titanium orstainless steel or of any bio-compatible metal or metal alloy or plasticmaterial. With respect to bio-compatible alloys, a NiTi alloy, forexample Nitinol, may be used. Other materials that can be used are, forexample, magnesium or magnesium alloys. Bio-compatible plastic materialsthat can be used may be, for example, polyether ether ketone (PEEK) orpoly-L-lactide acid (PLLA). Also the insertion device may be made of thesame material as the intervertebral implant or of another material.

Next, the operation of the intervertebral implant 1 and the insertiondevice will be explained. First, steps of connecting the insertiondevice 100 to the intervertebral implant 1 will be explained, withreference to FIGS. 10a to 11d . As shown in FIGS. 10a and 11a , theengagement portion 111 of the drive shaft 110 protrudes out of the frontportion of the guiding sleeve 120. The engagement portion 111 isoriented relative to the intervertebral implant in a manner such thatthe flat surfaces 113 are parallel to the upper and lower edges of theelongate opening 11. Such an orientation can be easily identified, forexample, when the positioning mark 114 is aligned with the position mark126 on the guiding sleeve 120. As further depicted in FIGS. 10b and 11b, the engagement portion 111 is inserted through the elongate opening11 into the recess 10 until the spherical surface portion 112 abutsagainst the corner of the recess 10. The cylindrical projections 122 ofthe guiding sleeve 120 enter into the recess 10, so that the sidewall 2can abut against the abutment surface 123 at the front portion of theguiding sleeve 120. In the insertion position shown in FIGS. 10b and 11b, the third abutment surface 23 of the intervertebral implant comes incontact with the abutment surface 123 of the guiding sleeve 120. Hence,the longitudinal axis L of the insertion device forms an angle of 45°with the central longitudinal axis LI of the intervertebral implant 1.

Next, as explained in FIGS. 10c and 11c , the drive shaft 110 isrotated, or tilted, in the spherical recess 12 in the intervertebralimplant 1, such that the flat surfaces 113 extend vertically in theintervertebral implant. In this orientation, the spherical portion 112of the engagement portion can pivot in the spherical recess 12 of theintervertebral implant 1. This rotation by 90° may be effected byactuating the button 135 at the handle.

Finally, as indicated by the straight arrow in FIG. 11d , the driveshaft 110 is pulled backwards. Thereby, the drive shaft 110 can move atleast partially between the cylindrical projections 122, which in turnenter further into the recess 10. When the engagement portion 111 isoriented vertically in the recess 10 and in the spherical recess 12,i.e., when the flat surfaces 113 extend parallel to the axis ofrotation, the engagement portion 111 cannot be removed from the recess10 through the opening 11. Also, if the engagement portion 111 isoriented vertically in the recesses 30, 30′, the engagement portion alsocannot be removed through the openings 31, respectively. At the sametime the abutment surface 23 of the intervertebral implant and theabutment surface 123 of the guiding sleeve 120 are pressed against eachother when the insertion device is tightened against the intervertebralimplant. Due to the flat abutting surfaces, a form-fit connection isprovided so that rotation, or more specifically pivoting, of theintervertebral implant relative to the insertion device is prevented. Byfinal tightening of the insertion device relative to the intervertebralimplant, the connection is locked.

FIGS. 12 to 18 show the different orientations that the insertion devicecan assume with respect to the intervertebral implant 1. In FIG. 12, thethird abutment surface 23 cooperates with the planar abutment surface123 provided on the guiding sleeve 120. In this position, the insertiondevice and the intervertebral implant form an angle of 45°. In FIGS. 13and 16, the intervertebral implant abuts with the second abutmentsurface 22 against the corresponding abutment surface 123 at the guidingsleeve 120. In this position, the insertion device and theintervertebral implant form an angle of 90°. In FIGS. 14 and 17 theintervertebral implant abuts with the first abutment surface 21 againstthe corresponding abutment surface 123 at the guiding sleeve 120. Inthis position, the insertion device and the intervertebral implant forman angle of 0°. In FIGS. 15 and 18, the intervertebral implant abutswith its cylindrical guiding surface 124 against the cylindrical guidingsurface 24 at the insertion device. As the surfaces permit pivoting ofthe implant relative to the insertion device, there may be a frictionalengagement which allows the insertion device to assume and be held atvarious angular positions relative to the implant. Each position can befixed by retracting the drive shaft 110, so that the engaging surfacesare pressed more tightly against each other. In this manner, theconnection can also be fixed by frictional clamping.

FIGS. 19 and 20 show the engagement of the intervertebral implantthrough the additional recess 30 in the front wall 2 a. FIGS. 21 and 22show the engagement of the intervertebral implant through the additionalrecess 30′ in the in the left sidewall 2 d. In these configurations, theimplant and the insertion device can be locked together in a singleposition.

Generally, in use, when the engagement portion 111 is in the 90° tiltedupright position, the engagement portion is freely pivotable around therotational axis R, so that a plurality of angular positions of theinsertion device relative to the interval implant can be adjusted andachieved. When the drive shaft 110 is retracted with the engagementportion 111 being in the upright position, the engagement portionpresses from inside against a wall of the recess 10 so that theinsertion device and the implant are pulled together. Thereby, variousangular positions can be fixed. With the abutment surfaces, predefinedangular positions, such as 0°, 90°, or 45° as shown in the exemplaryembodiment, can be fixed in a form-fit manner. Intermediate angularpositions may also be achieved by the aid of the guiding surfaces and aforce-fit connection. Loosening the fixation allows adjustments to therelative position between intervertebral implant and the insertiondevice without disconnecting the insertion device from the implant. Thismay be particularly useful for a lateral or anterior approach to theintervertebral space. The insertion device can be disconnected from theintervertebral implant by tilting the engagement portion 111 by 90° andremoving or detaching the engagement portion through the opening 11.

By means of the aforementioned steps, various access paths to anintervertebral space can be realized. Only by way of example, in asurgical TLIF method, a small incision is made near the center of theback of a patient. Access is made to the damaged disk, the disk isremoved, and the intervertebral implant filled with bone graft isinserted. The spinal segment is then stabilized, for example, usingpedicle screw and rods. The intervertebral implant and the insertiondevice according to embodiments of the invention open a variety ofpossibilities to engage the intervertebral implant and to insert theintervertebral implant into the intervertebral space. Once theintervertebral implant is finally implanted in the intervertebral space,the drive shaft is pushed forward again, tilted by 90°, and removed fromthe recess 10 or one of the recesses 30, 30′, respectively.

Turning now to FIGS. 23 to 25 a modified embodiment of theintervertebral implant is shown. The intervertebral implant 1000 is anALIF intervertebral implant that has a slightly modified innerstructure, specifically with respect to the solid body 3′, the top face5 a, and the bottom face 5 b. In addition, holes 1001 are provided thatare configured to receive screws 400 for engaging the adjacent upper andlower vertebral bodies, respectively. The intervertebral implant 1000also has the recess 10 with the elongate opening 11 as in the previousembodiment. The recess 10 may be provided at another side of thesidewall 2. An additional recess 300 in the middle of the front wall 2 aforms an alternate receiving portion for the insertion device. Therecess 300 is rotated by 90° compared to the recess 30 of the previousembodiment. In greater detail, the additional recess 300 extends withthe opposite long sides in a vertical direction. By means of this, thenecessary space for the recess 300 in the lateral direction can bereduced. This provides space for the additional holes 1001 for thescrews 400 to the left and to the right of the additional recess 300 onthe front wall 2 a.

Various other modifications of the implant and/or the insertion devicemay further be made without departing from the scope of the invention.

The intervertebral implant shown in the above-described embodiments isonly an example. The contour and shape of the intervertebral implant maybe different according to specific clinical requirements. For example,the contour may have any other shape, such as circular, rectangular,oval, kidney shaped, among others. In some embodiments, the height ofthe sidewall may be constant throughout the implant. The intervertebralimplant may also be in the form of a three-dimensional network or gridstructure that can be manufactured, for example, by 3D printingtechniques. In a further modified embodiment, the intervertebral implantmay be a dummy implant or testing implant that is used for a trialprocedure.

The number, orientation, and/or sequence of the abutment surfaces forgenerating a form-fit connection between the implant and the insertiondevice, and the number and/or position of the guiding surfaces is notlimited to those shown in the disclosed embodiments. Various otherabutment surfaces may be provided for adjusting the connection betweenthe intervertebral implant and the insertion device at various otherangles. The guiding surfaces may also be omitted.

In some embodiments, the elongate opening can be at another position.Still further, the elongate opening may extend vertically or at anincline. In some embodiments, more than one elongate opening with arecess for pivoting the implant relative to the insertion device may beprovided. Also, a number of additional recesses for receiving theinsertion device can be more or less than that shown in the describedembodiments.

While the present invention has been described in connection withcertain exemplary embodiments, it is to be understood that the inventionis not limited to the disclosed embodiments, but is instead intended tocover various modifications and equivalent arrangements included withinthe spirit and scope of the appended claims, and equivalents thereof.

What is claimed is:
 1. An intervertebral implant comprising: a bodyinsertable into an intervertebral space, the body comprising a firstface, a second face connected to and opposite the first face, and anaxis of rotation extending between the first face and the second face,wherein the body defines a hollow space between the first and secondfaces configured to accommodate an engagement portion of an insertiondevice, the hollow space being accessible from outside the body throughan opening formed between the first and second faces, wherein theopening is elongate and extends around the axis of rotation; whereinwhen viewed in a cross-section perpendicular to the axis of rotation,the intervertebral implant has an outer profile that defines theopening, wherein a portion of the outer profile that defines the openingextends circumferentially around the axis of rotation with a firstcontour configured to facilitate pivoting of the intervertebral implantrelative to the insertion device about the axis of rotation to a firstangular position and to a second angular position when the engagementportion of the insertion device is in the hollow space, a first abutmentsurface having a contour different from the first contour that engagesthe insertion device in a form-fit manner at the first angular position,and a second abutment surface having a contour different from the firstcontour that engages the insertion device in a form-fit manner at thesecond angular position; and wherein the first contour is furtherconfigured to engage the insertion device to hold the intervertebralimplant at at least one angular position different from the first andsecond angular positions.
 2. The intervertebral implant of claim 1,wherein the hollow space comprises a spherical portion.
 3. Theintervertebral implant of claim 2, wherein the axis of rotation extendsthrough a center of the spherical portion of the hollow space and issubstantially parallel to a sidewall that extends between the first andsecond faces.
 4. The intervertebral implant of claim 1, wherein the bodycomprises a solid portion and wherein the hollow space is formed by arecess in the solid portion.
 5. The intervertebral implant of claim 1,wherein the first abutment surface and the second abutment surface eachcomprises a planar surface.
 6. The intervertebral implant of claim 1,wherein at least one of the first abutment surface or the secondabutment surface is formed at a sidewall that extends between the firstand second faces.
 7. The intervertebral implant of claim 1, wherein atleast one of the first abutment surface or the second abutment surfaceis formed adjacent to the opening.
 8. The intervertebral implant ofclaim 1, wherein the first and second angular positions are arranged atabout 90° relative to each other.
 9. The intervertebral implant of claim1, further comprising a third abutment surface having a contourdifferent from the first contour that engages the insertion device in aform-fit manner at a third angular position different from the first andsecond angular positions.
 10. The intervertebral implant of claim 9,wherein the third abutment surface is located between the first abutmentsurface and the second abutment surface and corresponds to anintermediate angular position therebetween.
 11. The intervertebralimplant of claim 1, wherein the first contour of the opening forms aguiding surface configured to cooperate with a corresponding guidingsurface of the insertion device to hold the intervertebral implant in aforce-fit manner at one of a plurality of angular positions between thefirst and second angular positions relative to the insertion device. 12.The intervertebral implant of claim 11, wherein the guiding surface ofthe intervertebral implant is cylindrical.
 13. The intervertebralimplant of claim 1, wherein a sidewall that extends between the firstand second faces comprises two opposite long sides and two oppositeshort sides extending between the long sides, and wherein the opening isformed at a transition between one of the long sides and one of theshort sides.
 14. The intervertebral implant of claim 1, furthercomprising at least one further distinct opening configured to connectto the engagement portion of the insertion device at a fixed angularposition.
 15. A system comprising: the intervertebral implant of claim1; and the insertion device comprising: a drive shaft, wherein theengagement portion is formed at an end of the drive shaft; and a guidingsleeve configured to movably hold the drive shaft, the guiding sleevecomprising an abutment surface configured to abut against the first andsecond abutment surfaces of the intervertebral implant; wherein when theengagement portion is in the hollow space of the intervertebral implant,the insertion device can assume a first configuration where theintervertebral implant is pivotable relative to the insertion device,and a second configuration where the insertion device is tightenedagainst the intervertebral implant to fix the angular position.
 16. Thesystem of claim 15, wherein the guiding sleeve further comprises aguiding surface configured to engage the first contour of the opening.17. The system of claim 15, wherein the engagement portion has aspherical portion corresponding to a spherical shape of the hollow spaceof the intervertebral implant.
 18. The intervertebral implant of claim1, wherein when viewed in the cross-section perpendicular to the axis ofrotation, the first contour is curved.
 19. The intervertebral implant ofclaim 1, wherein when viewed in the cross-section perpendicular to theaxis of rotation, at least one of the first abutment surface or thesecond abutment surface has a flat contour, while the first contour isnot flat.
 20. An intervertebral implant comprising: a body insertableinto an intervertebral space, the body comprising a first face, a secondface connected to and opposite the first face, and an axis of rotationextending between the first face and the second face, wherein the bodydefines a hollow space between the first and second faces configured toaccommodate an engagement portion of an insertion device, a firstopening formed between the first and second faces that opens into thehollow space, and a second opening formed between the first and secondfaces that is spaced apart from the first opening; wherein the firstopening is elongate and extends around the axis of rotation tofacilitate pivoting of the intervertebral implant relative to theinsertion device about the axis of rotation when the engagement portionof the insertion device is in the hollow space; and wherein the secondopening is smaller than the first opening and is configured to connectto the engagement portion of the insertion device at a fixed angularposition.
 21. The intervertebral implant of claim 20, wherein theinsertion device is configured to interchangeably connect to either thefirst or second opening of the intervertebral implant.
 22. A method forinserting an intervertebral implant into an intervertebral space with aninsertion device, the intervertebral implant comprising a bodycomprising a first face, a second face connected to and opposite thefirst face, and an axis of rotation extending between the first face andthe second face, wherein the body defines a hollow space between thefirst and second faces configured to accommodate an engagement portionof the insertion device, the hollow space being accessible from outsidethe body through an opening formed between the first and second faces,wherein the opening is elongate and extends around the axis of rotation,and has wherein when viewed in a cross-section perpendicular to the axisof rotation, the intervertebral implant has an outer profile thatdefines the opening, wherein a portion of the outer profile that definesthe opening extends circumferentially around the axis of rotation with afirst contour configured to facilitate pivoting of the intervertebralimplant relative to the insertion device about the axis of rotation to afirst angular position and a second angular position when the engagementportion of the insertion device is in the hollow space, a first abutmentsurface having a contour different from the first contour that engagesthe insertion device in a form-fit manner at the first angular position,and a second abutment surface having a contour different from the firstcontour that engages the insertion device in a form-fit manner at thesecond angular position, and wherein the first contour is furtherconfigured to engage the insertion device to hold the intervertebralimplant at at least one angular position different from the first andsecond angular positions, the method comprising: inserting theengagement portion of the insertion device into the hollow space;adjusting the angular position of the intervertebral implant relative tothe insertion device; advancing the intervertebral implant into theintervertebral space; and removing the engagement portion of theinsertion device from the hollow space.